Piezo1 activation on microglial cells exacerbates demyelination in sepsis by influencing the CCL25/GRP78 pathway

BACKGROUND: In sepsis-associated encephalopathy (SAE), the activation of microglial cells and ensuing neuroinflammation are important in the underlying pathological mechanisms. Increasing evidence suggests that the protein Piezo1 functions as a significant regulator of neuroinflammation. However, the influence of Piezo1 on microglial cells in the context of SAE has not yet been determined. This study aims to investigate the role of Piezo1 in microglial cells in the context of SAE. METHODS: By inducing cecal ligation and puncture (CLP), a mouse model of SAE was established, while the control group underwent a sham surgery in which the cecum was exposed without ligation and puncture. Piezo1 knockout mice were employed in this study. Morris water maze tests were conducted between Days 14 and 18 postop to assess both the motor activity and cognitive function. A proteomic analysis was conducted to assess the SAE-related pathways, whereas a Mendelian randomization analysis was conducted to identify the pathways associated with cognitive impairment. Dual-label immunofluorescence and flow cytometry were used to assess the secretion of inflammatory factors, microglial status, and oligodendrocyte development. Electron microscopy was used to evaluate axonal myelination. A western blot analysis was conducted to evaluate the influence of Piezo1 on oligodendrocyte ferroptosis. RESULTS: The results of the bioinformatics analysis have revealed the significant involvement of CCL25 in the on...